On my speedlight I have several settings for multi flash, mostly to do with how many flashes and how fast they are fired.
When might you use multi flash? The only thing I can think of is cases where ...

In page #37 of the sppedlite 430exII manual, it says : Features available with type B cameras:
Manual flash, stroboscopic flash with wireless flash"
What the book means by "stroboscopic flash"
Isn't ...